As this kind of vehicle seat, a vehicle seat including a seat cushion and a seat back (seat component) are known (see Japanese Patent Publication No. 3335849). The seat component includes a frame member constituting a seat frame, a cushioning material constituting an outer shape of the seat, a through-hole of the cushioning material and a skin material having a bag shape and covering the cushioning material.
Here, the seat back includes an airbag and configurations relevant thereto (for example, a cleavage portion and a webbing). The cleavage portion is a weakened region of the skin material which is formed on a side portion (seated side) of the seat back and the airbag can bulge through the cleavage portion. The webbing is a cloth material (a relatively large cloth material) of a size according to the airbag. The through-hole is a hole portion that penetrates the cushioning material in a thickness direction and is formed near the side portion of the seat back.
In related art, the webbing is sewn to the back side of the skin material to reinforce the portion of the skin material other than the cleavage portion. At this time, the webbing passes through the through-hole of the cushioning material and is fixed to the frame member, while being located on the back side of the skin material. And, by the impact at the time of a vehicle collision, the airbag is bulged through the cleavage portion to protect an occupant. At this time, a bulging direction of the airbag is regulated (by reinforcing the portion of the skin material other than the cleavage portion with the webbing) and thus stress is concentrated on the cleavage portion, so that the airbag can be reliably bulged through the cleavage portion.
Further, in the seat component described above, a portion of the skin material can be attached to the cushioning material in a retracted form. The seat component includes a suspending wire, a fixing wire (an example of a reinforcing wire) and a ring member (a substantially C-shaped member).
The suspending wire is a rod-shaped member extending in a linear form and the fixing wire is a rod-shaped member which can be opposed to the suspending wire. The fixing wire is bent in a substantially transverse U shape at a midstream. Further, the ring member is a substantially C-shaped member and can be closed in a substantially O-shape by a tool, etc.
In the related art, the fixing wire is embedded in the cushioning material and partially exposed through groove portions of the cushioning material. The fixing wire extends in a vertical direction of the seat. At this time, interference of the fixing wire with the through-hole can be prevented owing to the bent portion of the fixing wire.
Then, the suspending wire is attached to a portion of the skin material and arranged so as to be opposed to the fixing wire. The suspending wire and the fixing wire are connected to each other by the ring member while a portion of the skin material is retracted into the groove portion of the cushioning material. Accordingly, the portion of the skin material can be fixed to the cushioning material in a retracted form.
However, in the related art, the strength of the cushioning material is partially decreased due to the through-hole of the cushioning material, and therefore, there is a risk that the sitting property of the seat is degraded.
Indeed, it is possible to slightly reinforce the cushioning material by arranging the fixing wire in close proximity to the through-hole. However, since the fixing wire has a bent shape, rigidity thereof is not enough.